The invention relates to a device capable of protecting the interior of ducts, pipes or conduits from vapor borne oils, grease and other particulate matter that may otherwise enter them via the openings at their end. The device preferably contains a reservoir for collecting particulate matter and an opening for admitting a wire or a cable into the piping. The wire or a cable is free to move in and out of the opening at all times.
In a preferred embodiment, the present invention may be used with the fusible link, fire detection units typically found in range hood suppression systems. Such fusible link detection systems are typically installed at strategic locations within the hood or duct assemblies of commercial kitchens and serve as fire safety measure that is typically a requirement of building codes. These fusible link detection systems are usually installed above the kitchen appliances and under the exhaust duct openings.
A fusible link detection system typically consists of a length of taut cable, one end of which is connected to a suppression system control head, with the other end fixed to a manually releasable activation switch. The term “fusible link” refers to one or more sections of the cable that are designed to melt when the temperature inside the ductwork, or the range hood exhaust system, reaches or exceeds a critical level that may be indicative of an out of control fire in the range. When the fusible link melts, the cable or wire may slacken, causing the control head to release a fire suppression agent through the system. In a typical fusible link detection system, the cables are protected by piping, with only the fusible link sections being exposed directly to the cooking fumes being vented by the range hood.
However, some of the cooking fumes may enter the protective piping surrounding the cable. These fumes typically carry oil, grease and flammable particulate matter. Over time this oil and grease may accumulate on the inside of the pipes, on the cable and on the pulleys that guide the cable around bends in the pipe work. This buildup of oil and grease is not only a fire hazard, but may rust the pipes from the inside and may also jam the corner pulleys. The buildup of residue on the cable and on the pulley may prevent the cable from slacking even if the fusible links melt so that the fire suppression agent is not released even in the event of an out of control fire.
Because of these hazards, fire safety codes typically require that the range hood fire suppression systems and their hoods and ducts be inspected regularly. However, even if a dangerous buildup is detected, the residue is difficult to remove. The proper method would be to remove and replace the protection pipe work. This may be a costly undertaking as it typically requires the restaurants to close for the duration of the work is being performed.
The present invention is intended to prevent grease and particular buildup inside the piping and make fire suppression systems more reliable. The device contains an opening to admit the cable used in the fusible link system. There may be filtered openings for fumes as well. Alternatively, the device may simply shield an opening or a duct from grease like buildup without having an opening for a fuse link cable.
Additionally, the present invention offers a collecting or settling surface for the congealing agents. Therefore, rather than settling back down onto the cooking surfaces the rejected particles are removed from the kitchen all together when the component is replaced by the certified technician; it may be removed from the area and discarded appropriately. In this way, a critical grease buildup is easy to detect if maintenance is not performed since it is likely visible from the outside and the problem is easily rectified by either removing the residue from the outside surface of the present invention or by replacing the cover entirely. The relative simplicity of the device and the labor involved will significantly reduce the time and expense involved with effectuating the required maintenance.